It's not "old text editors". There are current tools for viewing source (pull requests/diffs a prime example) that are extremely good at what they do but are language agnostic. As is so often said, code is read more than it's written. If I can't understand the source without pulling it into my IDE, that adds a lot of friction to these reading tasks.
Those other tools you work with can become more advanced to in order to keep up with the improvements your IDE offers. You want to inline a diagram to your code? That image should show up both in your editor and in the diff.
Expecting your teammates to use an IDE does not get it the way of working in a team. In my experience as a team we have a default IDE for everyone to use and a configuration file for it so everyone's is using the same settings. Usually you could use a different IDE if you could configure it to act similar, but making sure everyone uses the same tools doesn't prevent you from working as a team.
